class GoogleChart::LineChart

Generates a Line chart. An option can be passed that allows you to create a Line XY Chart

Examples

# Line Chart
lc = GoogleChart::LineChart.new('320x200', "Line Chart", false)
lc.data "Trend 1", [5,4,3,1,3,5,6], '0000ff'
lc.data "Trend 2", [1,2,3,4,5,6], '00ff00'
lc.data "Trend 3", [6,5,4,3,2,1], 'ff0000'
lc.axis :y, :range => [0,6], :color => 'ff00ff', :font_size => 16, :alignment => :center
lc.axis :x, :range => [0,6], :color => '00ffff', :font_size => 16, :alignment => :center

# Line XY Chart
lcxy =  GoogleChart::LineChart.new('320x200', "Line XY Chart", true)
lcxy.data "Trend 1", [[1,1], [2,2], [3,3], [4,4]], '0000ff'
lcxy.data "Trend 2", [[4,5], [2,2], [1,1], [3,4]], '00ff00'
puts lcxy.to_url

Attributes

is_xy[RW]

Public Class Methods

new(chart_size='300x200', chart_title=nil, is_xy=false) { |self| ... } click to toggle source

Specify the

  • chart_size in WIDTHxHEIGHT format

  • chart_title as a string

  • is_xy is false by default. Set it to true if you want to plot a Line XY chart

# File lib/google_chart/line_chart.rb, line 28
def initialize(chart_size='300x200', chart_title=nil, is_xy=false) # :yield: self
  super(chart_size, chart_title)
  self.is_xy = is_xy
  @line_styles = []
  yield self if block_given?
end

Public Instance Methods

is_xy=(value) click to toggle source

Pass in true here to create a Line XY.

Note: This must be done before passing in any data to the chart

# File lib/google_chart/line_chart.rb, line 38
def is_xy=(value)
  @is_xy = value
  if value
    self.chart_type = :lxy
  else
    self.chart_type = :lc
  end
end
line_style(data_set_index, options={}) click to toggle source

Defines a line style. Applicable for line charts.

data_set_index

Can be one of :background or :chart depending on the kind of fill requested

options

: Options for the style, specifying things like line thickness and lengths of the line segment and blank portions

Options

  • :line_thickness (mandatory) option which specifies the thickness of the line segment in pixels

  • :length_segment, which specifies the length of the line segment

  • :length_blank, which specifies the lenght of the blank segment

# File lib/google_chart/line_chart.rb, line 55
def line_style(data_set_index, options={})
  @line_styles[data_set_index] = "#{options[:line_thickness]}"
  @line_styles[data_set_index] += ",#{options[:length_segment]},#{options[:length_blank]}" if options[:length_segment]
end
process_data() click to toggle source
# File lib/google_chart/line_chart.rb, line 60
def process_data
  if self.is_xy or @data.size > 1
    if self.is_xy # XY Line graph data series
      encoded_data = []
      @data.size.times { |i|
        # Interleave X and Y co-ordinate data
        encoded_data << join_encoded_data([encode_data(x_data[i],max_x_value), encode_data(y_data[i],max_y_value)])
      }
      join_encoded_data(encoded_data)
    else # Line graph multiple data series          
      join_encoded_data(@data.collect { |series|
                          encode_data(series, max_data_value)
                        })
    end
  else
    encode_data(@data.flatten, max_data_value)
  end
end